Title (en)

MULTIPLYING SYSTEM

Publication

EP 0497622 A3 19930303 (EN)

Application

EP 92300856 A 19920131

Priority

JP 3244491 A 19910131

Abstract (en)

[origin: EP0497622A2] A multiplying system based on the Booth's algorithm, comprises a Booth's decoder having a first input receiving a multiplier "Y" and a second input receiving a mode signal designating either a first multiplication of "X x Y" (where "X" is a multiplicand) or a second multiplication of "-X x Y". The Booth's decoder generates a Booth's decoded value and a sign selection signal to a partial product generation circuit which also receives the multiplicand "X", so that the partial product generation circuit generates either a first partial product of "X x Y" or a second partial product of "-X x Y" in accordance with the sign selection signal. An output of the partial product generation circuit is summed by a partial product summing circuit, and an output of the partial product summing circuit is added to a value "A" stored in an output register by an arithmetic unit. Thus, the accumulating accumulating multiplication "A = A +/- X x Y" can be executed in the same hardware without using a circuit for sign-inverting the output of the partial product summing circuit. <IMAGE>

IPC 1-7

G06F 7/544; G06F 7/52

IPC 8 full level

G06F 7/533 (2006.01); G06F 7/52 (2006.01); G06F 7/53 (2006.01); G06F 7/544 (2006.01)

CPC (source: EP US)

G06F 7/5338 (2013.01 - EP US); G06F 7/5443 (2013.01 - EP US)

Citation (search report)

• [A] ELECTRO/87 AND MINI/MICRO NORTHEAST CONFERENCE RECORD vol. 12, 1987, NEW YORK US pages 11-2-1 - 11-2-7 LEIBOWITZ 'DESIGNING WITH SUB 15 NANOSECOND MULTIPLIERS AND MULTIPLIER-ACCUMULATORS'
• [A] MONTOYE R. K., ET AL.: "AN 18NS 56-BIT MULTIPLY-ADDER CIRCUIT.", IEEE INTERNATIONAL SOLID STATE CIRCUITS CONFERENCE., IEEE SERVICE CENTER, NEW YORK, NY., US, 14 February 1990 (1990-02-14), US, pages 46 - 47 + 262., XP000201824, ISSN: 0193-6530, ISBN: 978-1-4799-0918-6, DOI: 10.1109/ISSCC.1990.110122

Designated contracting state (EPC)

DE FR GB

DOCDB simple family (publication)

EP 0497622 A2 19920805; EP 0497622 A3 19930303; EP 0497622 B1 19981209; DE 69227791 D1 19990121; DE 69227791 T2 19990506; JP 3033212 B2 20000417; JP H04246723 A 19920902; US 5303178 A 19940412

DOCDB simple family (application)

EP 92300856 A 19920131; DE 69227791 T 19920131; JP 3244491 A 19910131; US 83040092 A 19920131